A data warehouse can be used to store data used for reporting and analysis, and can be organized into dimension tables and fact tables. A fact table is a table that can store fact data, typically numerical, about the state of a specific process. A dimension table (or “dimension”) is a table that can store dimension data about a context in which the specific process is performed. In a typical business data warehouse, fact data can include data such as sales and inventory, and dimension data can include data such as date and store. Each data record in a fact table can have one or more foreign keys which can relate the data record to each dimension. Thus, for example, a specific sales transaction can have foreign key values that associate the specific sales transaction to a specific date and store.
As an example of a data warehouse, Oracle Clinical Development Analytics (“OCDA”) is an analytics application that can provide dashboards containing tables and graphs that present actionable information about clinical operations and data management. OCDA's reports are drawn from a data warehouse, where the data warehouse is populated from one or more source transactional databases (or “source databases”), such as Oracle Clinical (“OC”) and Siebel Clinical (“SC”).
The OCDA data warehouse can store one or more fact data records concerning several processes, such as conducting clinical trials, getting sites prepared to conduct a study, enrolling subjects, collecting data from subjects, cleaning subject data, or recording monitoring visits. Each fact data record can relate to several dimensions, such as date, study, site, and investigator.
In the case of the OCDA data warehouses (and typical of data warehouses in general), each fact data record originates from only one source transactional database. But each source transactional database may carry its own copy of a dimension data record describing the same entity. For example, a single investigator can be present in both a study management database (such as the SC database), and the data management database (such as the OC database).